Vat dyestttff and process of making same



Reisaued Apr. 24', 1928. Re.

UNITED STATES PATENT OFFICE.

JOSEIH GHDINWIDDIE, OF PENNS GROVE, NEW JERSEY, ASSIGNOR TO E. I. DU FONT DE NEMOURS & COMPANY, OF WILMINGTON, DELAWARE, A CORPORATION OF DELAWARE. a

VAT DYESTUFF AND PROCESS OF MAKING SAME.

No Drawing. Original No. 1,558,252, dated October 20, 1925, Serial No. 1,153, filed January 8, 1925.

Application for reissue filed December 2, 1926. Serial No. 152,241.

stirring for at least five minutes with a solution, in'an inert solvent such as benzene, of the molecularly equivalent amount of 2-hydroXy-3-niethyl-5-chloro-thionaphthene. \Vhen suflicient time, say-half an hour, has elapsed to insure that the-reaction is completed, the'dyestufi is filtered off, washed with a solvent such as benzene, then with alcohol and finally dried in an oven at 5060 C. The dyestuff in powder form has This invention relates to violet vat dyestuffs resulting from the condensation of a halo-isatin-chloride with an 'hydroxy-methyl-halo-thionaphthene, and to the process of their production. Particularly it relates to the condensation of dibromisatin-chloride with 2-hydroxy-3-methyl-5-chloro-thionaphthene, having the formula:

0 a brilliant red-blue shade; it may be used 0/ in the form of powder or may be made into 0 a paste for greater ease in dissolving. Said dyestufl' dyes cotton from a yellow orange hydrosulfite vat a bright full shade of violet of very good fastness to light, washing, chlorine, etc. i

The temperature at which the reaction between the dibromisatin and the thionaphthene derivative is carried on is, within wide limits, immaterial. The dyestufl has been made with the benzene solution of 2- hydroXy-3-methyl5-chloro-thionaphthene at room temperature, 20 C., and" the dibromisatin chloride solution in chlor-benzene varying from room temperature to the boilingpoint 'of Inono-chlor-benzene, which is 132 C. In the condensation of dibromisatin with phosphorus pentachloride, hydrochloric acid is split off as is also the case during the condensation of the dibromisatin-chloride with 2-hydroXy-3-methyl-5-chloro thionaphthene. The reactions which occur are probably as I German Patent No. 193,150 describes a violet dyestufi' produced by condensing isatin chloride with 2-hydroxy-thionaphthene and subsequently brominating this condensation product in nitro-benzene, sulfuric acidor other inert solvent.

By the process described below a new dye is obtained, which has properties superior to that described in German Patent No. 193,150 in regard tobrightnesashade and tinctorial value.

My invention may be illustrated by the following specific example:

Heat under reflux with mono-chlorobenzene or another suitable inert solvent 10.35 parts of dibrolnisatin together with a slight excess of phosphorus pentachloride (for example, with 8.52 parts of the commercial product) until a clear red brown solution is obtained. This solution is mixed with good follows:

i 0 Br Br tJ l 1 n PO o -o1 POO HO 0 h M Dlbromlsatln Phosphorus Pentachloride Dibromisatln chloride P001; H01

on, o o s +1.0. N s 01 Violet dyestufl.

o on B t o1 t n if s 01 Dibromisatln chloride 2-hyd.roxy-3- methyl-B-chloro-thionaphthene,

Although in the above example certain mentioned, it will beunderstood that my inspecific conditions of operation have been vention 1s not limited thereto, but that the .certain specific compounds are mentioned in the above example, the invention is not limited thereto but that obviously any halogenated isatin-chloride having the general formula:

' in which one or more of the positibns Y are occupied by halogen may be employed for coupling with any hydroxy-methyl-halothionaphthene of the general formula:

are occupied by the methyl group and one 'or more are occupied by halogen.

The new dyestuffs above described are chiefly useful in the dyeing of cotton, but they may also be used to advantage in the dyeing of wool and silk.

' I claim:

1. The process of producing a vat dyestufi which comprises condensing a halogenated isatin-chloride with one molecularly-equivalent amount of an hydroxy-methyl-halothionaphthene.

2. The process of producing a vat dyestufi which comprises condensing a halogenated isatin-chloride with one molecularly-equivalent amount of' 2-hydroxy-3-methyl-5- chloro-thionaphthene.

3. The process of producing a vat dyestufi which comprises mixing a solution of dibromisatin-chloride in an inert solvent, while stirring, with a solution in an inert solvent, of 2hydroxy-3-methyl-5-chlorothiona'phthene,'and filtering and drying the precipitate.

precipitate formed.

4. The process which comprises heating 10.35 parts of dibromisatin dissolved in an inert solvent under a reflux condenser with about eight parts of phosphorus pentachloride until a clear red-brown solution is obtained, mixing this solution, while stirring, with a solution of 2-hydroxy-3-methyl- 5-chloro-thionaphthene, and recovering the 5. As a new compound a vat dyestuflt' having the general formula:

Y o o o o x Y NH s x wherein one or more of the positions Y are occupied by a halogen and one or more of the'positions X are occupied by a methyl group and one or more of the positions X by a halogen which compound,

when dried, is a'violet powder dyeing cotton from a hydrosulfite vat to a violet color.

6. As a new compound a vat dyestufl having the general formula:

wherein one or more of the positions Y are occupied by a halogen, the others being occupied by hydrogen, and one or more positions X are occupied by the methyl group and one or more by a halogen, the others being occupiedby hydrogen.

7. As a new composition of matter, a product obtainable by condensing a dibromisatin-chloride with '2-hydroxy-3-methylfi-chloro-thionaphthene, and having most probably the following graphical formula:

8. A dyestufi obtainable by condensing a halo-isatin-chloride with a molecularlyequivalent amount of an hydroxy-methylhalo-thionaphthene. I

9. A dyestufl obtainable by condensing a di-halo-isatin-chloride With an hydroxy- Inethyl-halo-thionaphthene, and purifyin the resulting condensation product. sai dyestufl dyeing cotton from a hydrosulfite vat a violet color of excellent fastness to light, washing, and chlorine.

10; As a. new composition of matter, a product obtainable by condensing a dibromisatinchloride with 2-hydroxy-3-methyl- 5-chloro-thionaphthene, said product having, in powder form, a brilliant red-blue shade, and dyeing cotton fiber from a yellow orange hydrosulfite vat a bright full shade of violet of excellent fastness to light, washing, and chlorine.

In testimony whereof I afiix my signature.

JOSEPH G. DINWIDDIE. 

